Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

First Direct “Chemical Fingerprint” of an Exoplanet orbiting a Sun-Like Star

13.01.2010
Astronomers have obtained the first direct spectrum – a “chemical fingerprint” – of a planet orbiting a distant, Sun-like star, providing direct data about the composition of the planet's atmosphere.

Such “chemical fingerprinting” is a key technique in the search for habitable planets around other stars. As such, the result represents a milestone in the search for life elsewhere in the Universe. More directly, results like this are expected to provide new insight into how planets form.


Image of the HR 8799 system. In the center, the host star HR 8799. Further investigation shows that three of the specks surrounding the star are planets (marked): Starting at 11 o\'clock, clockwise: HR 8799b, HR8799c and HR8799d. The other specks and patterns are artefacts, which are unavoidable in a challenging observation like this one – star and planets are extremely close, and the star is a few thousand times brighter than the planets. The distance from the star to HR 8799c corresponds to 38 times the average Earth-Sun distance. Image credit: MPIA / W. Brandner

The search for life on other planets is one of the most exciting endeavours of modern astronomy. Over the past decade, astronomers have discovered more than 400 exoplanets (that is, planets orbiting stars other than the Sun). In order to judge a planet's habitability, or even detect tell-tale traces of habitation, astronomers need to do more than just detect such planets: They need to find out what the planet – more specifically, its atmosphere – is made of. To this end, they need to obtain the planet's spectrum, a “chemical fingerprint” that can be measured by examining the light received from the planet. Now astronomers have, for the first time, measured the spectrum of an exoplanet orbiting a Sun-like star directly – an important step in the ongoing search.

The research team, which includes three researchers from the Max Planck Institute for Astronomy (MPIA) and two from Canadian universities, studied the planetary system around the bright, very young star HR 8799, 130 light-years from Earth, located within the constellation Pegasus. The planetary system resembles a scaled-up version of our own Solar System and includes three giant planets, which had been detected in 2008 in another study. “Our target was the middle planet of the three, which is roughly ten times more massive than Jupiter and has a temperature of about 800 degrees Celsius,” says team member Carolina Bergfors (MPIA), who participated in the observations as part of her PhD work. The researchers recorded the spectrum using the NACO instrument installed at the European Southern Observatory's Very Large Telescope (VLT) in Chile, in particular its combined camera/spectrograph CONICA, which was developed at the MPIA and at the Max Planck Institute for Extraterrestrial Physics.

As the host star is several thousand times brighter than the planet, and the two are very close, obtaining such a spectrum is an immense feat. Markus Janson of the University of Toronto, lead author of the paper reporting the new findings, explains: “It's like trying to see what a candle is made of, by observing it next to a blinding 300 Watt lamp – from a distance of 2 kilometres [1.3 miles].” Carolina Bergfors (MPIA), whose work on this project is part of her PhD studies, adds: “It took more than five hours of exposure time, but we were able to tease out the planet's spectrum from the host star's much brighter light.”

In time, the astronomers hope that this technique will help them gain a better understanding of how planets form. As a likely first step, they aim to record the spectra of the two other giant planets orbiting HR 8799 – which would represent the first time that astronomers would be able to compare the spectra of three exoplanets that form part of one and the same system. As a much more distant goal, the technique will allow astronomers to examine exoplanets for habitability, or even signs of life.

More immediately, the results pose something of a challenge to current models of the exoplanet's atmosphere. “The features observed in the spectrum are not compatible with current theoretical models,” explains MPIA's Wolfgang Brandner, a co-author of the study. “We need to take into account a more detailed description of the atmospheric dust clouds, or accept that the atmosphere has a different chemical composition than previously assumed.”

Contact information

Dr. Wolfgang Brandner (Coauthor)
Max Planck Institute for Astronomy, Heidelberg, Germany
Phone: (0|+49) 6221 – 528 289
E-mail: brandner@mpia.de
Dr. Markus Pössel (PR)
Max Planck Institute for Astronomy, Heidelberg, Germany
Phone: (0|+49) 6221 – 528 261
E-mail: poessel@mpia.de
Background Information
The results described here have been published as M. Janson et al., "Spatially resolved spectroscopy of the exoplanet HR 8799 c", Letter to Astrophysical Journal.

The team is composed of M. Janson (University of Toronto, Canada), C. Bergfors, M. Goto, W. Brandner (Max-Planck-Institute for Astronomy), and D. Lafrenière (University of Montreal, Canada).

Dr. Markus Pössel | Max-Planck-Institut
Further information:
http://www.mpia.de
http://www.mpia.de/Public/menu_q2.php?Aktuelles/PR/2010/PR100112/PR_100112_en.html

More articles from Physics and Astronomy:

nachricht Climate cycles may explain how running water carved Mars' surface features
02.12.2016 | Penn State

nachricht What do Netflix, Google and planetary systems have in common?
02.12.2016 | University of Toronto

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>